sceptic

n. 怀疑(论)者,多疑的人

The government must still convince the sceptics that its policy will work.

政府仍须使持怀疑态度的人相信其政策可行.

The government must still convince the sceptic that its policy will work.

政府仍须使持怀疑态度的人相信其政策可行。