Nowadays, _______ cars are more and more popular.

Tom was __________ a happy childhood, ______ most people would like to have.

 I’m always ________ about what I say because careless remarks are likely to hurt others’ feelings.

Einstein’s Theory of Relativity is so ________that most of us can not understand it.

A lot of praises have come from those _____ patients because they are getting better after taking the medicine.