I was revising my notes today. Came across a handy tip. So, thought to share it: Never mix verb forms.

Be careful with below constructions.
X is Y
X seems Y
X has remained Y

such constructions are a form of comparison and X and Y in these constructions should strictly follow rules of parallelism i.e. X and Y should be grammatically as well as structurally parallel.

consider the following examples:

To welcome each day wholeheartedly is embracing life fully incorrect - infinitive + gerund
welcoming each day wholeheartedly is to embrace life fully incorrect - infinitive + gerund
To welcome each day wholeheartedly is to embrace life fully correct - infinitive + infinitive
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My 2 cents as well..

"According to the teachings of the Buddhist and Hindu religions, attaining nirvana is to enter a state of supreme liberation"

"attaining nirvana" is not parallel to "to enter". This could be corrected in 2 ways.

1) According to the teachings of the Buddhist and Hindu religions, to attain nirvana is to enter a state of supreme liberation. OR

2) According to the teachings of the Buddhist and Hindu religions, attaining nirvana is entering a state of supreme liberation
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