单选题

34、It may not be a good habit to look up the dictionary whenever you ________a difficult word while reading.

A
come at
B
come across
C
come along
D
come up
参考答案  
B
题目详解：
177****7933
come across遇见
158****0432
come across something or someone, you find them or meet them by chance.
158****0432
PHRASAL VERB When something or someone comes along, they occur or arrive by chance.
136****3830
Acome at 扑向，攻击 B.come across使…印象，偶然发现遇见 C.come along一起参加活动 D.come up 发生，走近
134****6392
这个应该选B吧，当你遇到一个难的单词就去查字典 这可能不是一个好习惯 。