It is doubtful______the work can be completed on time.A．ifB．whyC．thatD．when

It is doubtful whether anyone can be a truly ______ observer of events.A．inadequateB．impas

It is advisable that the working mother______a balance between work and family life.A．make

I am doubtful whether I can solve the puzzle, but I ’llhave a ____ at it.A) shootB)

The ratio of the work done by the machine______________the work done on it is called the

It is advisable that the working mother______a balance between work and family life.A.make

A: Must we finish the work right now?B: No you _______. You can do it tomorrow.A.needn