You _______ ever saw computers years ago, but now they are everywhere.

My father has a lot of things to do. He has little time to rest. He always feels  .

Jim is good at maths, but his physics is _________.

--- What about going hiking this weekend?---Sounds good. The weather is _____.

Traveling around big cities by taxi can cost a lot of money, but it's usually        to take the underground train to most places.