Question

1. Have you checked out our school website lately?
2. Have you lately checked out our school website?
(What is the suitable position of the adverb 'lately'?)

3. Is there something that/which I should see?
(Do you prefer 'which' to 'that' in this sentence?)

4. Mina sent me a message that she uploaded the pictures.
('a mesage' and the that clause is in apposition, right? What is the part of speech of the that clause? Is the that clause a noun clause or an adjective clause which modify 'a message'?)

Answer 1

#1 is far better than #2. Usually, adverbs should be as close to the verb as possible, but not with a phrasal verb and not before the phrasal verb.

For #3, I'd just skip "that" or "which" entirely! But if you need to use one, then use "that."

The "that" clause in 4 is a noun clause, and yes, serving in apposition to "message." In the "that" clause, however, I'd say "had uploaded" since the main verb is already in the simple past.