Question

1. Hold this pose, then return your leg to the ground and your arms to the sides.

2. Hold this pose, and then return your leg to the ground and your arms to the sides.

3. Hold this pose. Then return your leg to the ground and your arms to the sides.

4. Hold this pose. Then, return your leg to the ground and your arms to the sides.
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Which ones are grammatical? Are they all grammatical? Do we have to put a comma after 'Then'?

Answer 1

2 and 3 are correct.

Answer 2

1 through 3 are fine. No, you do not need the comma after "then". #2 does not need "AND" before "then", but it's not really wrong.

Answer 3

1 is not correct because "then" is not a coordinating conjunction. See your other post.

Answer 4

I disagree. I'm looking in Walsh:
"The conjunctive adverbs such as <i>however, then, therefore, still<I/> also connect independent clauses."</i>

Answer 5

... with semicolons.