The answers are 2 and 3.
Sentence 2: One of the uses of the colon is to introduce an item or a series of items. These items, <em>after the colon</em>, are written with <em>lower case.</em> "Thats the other thing I leaned<em>: being active</em>..."
Sentence 3. If a quotation contains <em>two or more sentences</em>, we use a <em>colon</em>. The two i<em>ndependent clauses</em> in the quotation <em>are connected by a semicolon.</em>
The correct answer is a because the second word in the sequence is what word most closely relates to the sense before it.
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