daʊt noun
3
if/when (you’re) in doubt
used when advising someone what to do if they are uncertain about something 如(你)无把握,如(你)有怀疑〔用于建议〕
如有疑虑就咨询你的医生。
6
without doubt
used to emphasize an opinion 确实,的确〔用于强调某个观点〕