The burning of fossil fuels and of tropical forests releases so much c

OFFICIAL EXPLANATION


THE PROMPT
• Concepts tested?
→ contrary-to-fact situations (hypotheticals) and the correct verb tense
→ modifier type and placement
→ verb tenses

THE OPTIONS
• ordinarily is a code word for a "contrary-to-fact" or "hypothetical" situation
→ Although carbon dioxide traps a significant amount of the sun's heat, ordinarily (usually, typically, normally) that heat would escape

• Hypothetical statements are traditionally categorized as Type II conditionals
Conditional, Type II: IF simple past, THEN present conditional (would)
This way: IF the carbon dioxide did not trap a significant amount of the sun's heat, THEN that heat WOULD escape.
→ in a Type II conditional, the time is now or any time and the condition is unreal (contrary to fact or hypothetical)
(*See footnote for a condensed version of the five major conditional types.)

• if you see a verb split between would and will in the answer choices, you should immediately look for a hypothetical situation
→ the correct verb for the result clause (the THEN clause) is would

• which is correctly preceded by a comma and correctly modifies heat

• I see no errors
KEEP
• will is not used for hypotheticals.
→ the correct verb is would
→ a statement of fact in simple present tense can be followed by a hypothetical statement that uses would

• will is used for simple future situations, of course, but also for predictions
If Yanni does not study for the test, he will not pass it.

• this time, ignore has become. You can already eliminate B.
→ has become is not quite right.
→ If we were talking about an event in the recent past that continues into the present, we would probably need to use have released and has become
Verbs can shift tenses and still be parallel, but in this case, becomes is more consistent with the first part of the sentence than is has become

• we are dealing with a hypothetical situation and need would: if human beings were not polluting the air, then the sun's heat would escape (and Los Angeles would not be coping with 121°F heat)
ELIMINATE B

• the word that, which modifies the noun heat, is almost never separated from its noun by a comma
→ the word that introduces essential information about a noun that cannot be set off by a comma
• as in B, will is not the correct verb tense. We use would to describe situations that are contrary to fact.
ELIMINATE C
D) becomes trapped that would ordinarily have escaped into space
• the noun modifier should be placed right after the subject (heat), not right after the verb (becomes trapped)

• Never place only a comma between a subject (heat) and a verb (becomes)
→ Never.
Correct: Sonia climbs mountains.
Always wrong: Sonia, climbs mountains.

• the that-clause is placed too far from its noun, heat
→ the Modifier "Touch" rule states that noun modifiers should be as close as possible to their nouns
→ that tells us something important about the noun and should be placed before the verb
ELIMINATE D

[/quote]
• as in D, the modifier for heat (that would ordinarily escape) is too far from its noun
• again, ignore has become, and if you are worried, compare this option to option A.
No contest. Option A is better.
ELIMINATE E

The answer is A.

COMMENTS

I am playing catch up and will be doing so for the next few days.
In fact, I must go back even further that this post.
Judging the Heroes of Timers competition was fun, challenging, and time-consuming.

I am happy to see my Butler crew and your posts.

A couple of these explanations are excellent. The others are very good.
Explaining what is wrong with the incorrect options is difficult.
Nice work.


***VERY condensed summary of conditionals

Zero conditional: If THIS thing happens, THAT thing happens.
-- general truths
-- IF simple present, THEN simple present
-- situation is real and possible. True now and always.

Type 1: If THIS thing happens, THAT thing will happen
-- statements in the present made about the future and about real things
-- IF simple present, THEN simple future
-- condition is real, outcome ("truth") is very probable

Type 2: If THIS thing happened, then THAT thing would happen
-- If you left the house earlier, then you would be on time for the bus.
(But you did not leave the house earlier.)

Type 2: If THIS thing were to happen, then THAT thing would happen
-- If antitrust laws were enforced properly, then oligopolies would not control entire sectors of the economy.
-- hypothetical (theoretical) statements NOT based on what is actual. Counterfactual, unreal, imaginary (hypothetical)
-- IF simple past, THEN present conditional (or present continuous conditional)
-- the condition is unreal. The time is now or any time

Type 2 (with present continuous conditional): If THIS thing happened, then THAT thing would be happening
-- If I understood the joke, I would be laughing. (But I don't understand the joke, so I am not laughing.)

Type 3: If THIS thing had happened, then THAT thing would have happened. (But neither thing happened.)
-- IF past perfect, THEN perfect conditional (would + have + verbED)
-- If they had cooperated better, then they would have finished their project on time. (But they didn't cooperate, and they didn't finish on time.)
-- statements about the unreal past and probable result (often statements of regret or missed opportunity)
-- unreal past condition, probable result in the past that is also unreal (the result did not happen)

Mixed conditional: If THIS thing had happened, then THAT thing would happen
-- IF is in the past, THEN is in the present (present result of a past action)
-- If past perfect, THEN present conditional (just as in Type 2)
-- time is an event in the past, result is ongoing [affects the present]
-- If I had taken the Series 7, I would be a stockbroker. (But I didn't take the tests and I am not a stockbroker.)
(Mixed conditionals have many variations. I've just listed what seems to be the most common type.)