| 词组 | doubtful |
| 释义 | 1．doubtful 有时作“使人怀疑的”解，有时作“怀疑的”解，如 Here is a doubtful point of grammar 和 I am doubtful of the construction of this sentence 注意第二句里 doubtful 后面接 of。 2．doubtful 除了在否定句和疑问句里以外，后面通常接 whether 而不接 that，如通常说 It is not doubtful that he will come soon 和 Can it be doubtful that he will come soon? 但不说 It is doubtful that he will come soon。最好把 that 改作 whether。 3．It is doubtful whether he will come soon 含有“他大约不会不久就来”的意思，It is doubtful whether he will not come soon 含有“他大约不久就来”的意思。 4．doubtful（怀疑的）后面可以不用介词而直接以 what，where，how 等开首的短语或从句。例如： I am doubtful what to do with it. I am doubtful where he lives. I am doubtful how to proceed. |
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