ifconjunction
It is doubtful whether the government will ever accede to the nationalists' demands for independence.政府不太可能会同意民族主义者的独立要求。
It is doubtful if it will be possible to carry through the reforms.

SMART Vocabulary: related words and phrases

Uncertainty
amorphous
be neither fish nor fowlidiom
blurringly
blurry
circumstantial
indeterminacy
indeterminate
indeterminately
insecurely
insecurity
murky
shakiness
shallowly
slippery
spec
squishy
wavery
wifty
wishy-washy
you never knowidiom