[ltcuoi]

What we have said to this point makes it sound like tense shifting is a bad thing.

Question for the above sentence: Shouldn't sound be sounds?

My second question is to whether or not I should use a past or present tense to make this generalization. A friend of mine did something nice to me last week. I saw her today, should I say "It was nice of you to do such and such to me last week" or "It is nice of you to do such and such".

Thanks in advance for answering these questions, which has been bogging me down.