1 . You must be _______(谨慎的) when using this product, since incorrect use can have a negative effect.

2 . When it comes to second hand cars, one has to be as c_____________ as possible about the condition of them.

3 . My boss advised me to be__________when making a decision,adding that it was not wise to put all the eggs in one basket.

A．aggressive

B．cautious

C．determined

D．influential

4 . I am _______ about what I say because careless remarks are likely to hurt others’ feelings.

A．enthusiastic	B．concerned
C．doubtful	D．cautious