(1)惟恐，以免(for fear that;so that... not)(fml)：They spoke in whispers～they (should，might) wake him. 他們輕聲說話，唯恐吵醒他。She took her umbrella～it (should) rain. 她帶了雨傘以備下雨。Write the message down～you forget it. 把這口信記下來免得你忘了。
(2)(用于fear，be afraid，be anxious等之后，相當于that)(fml)：She fears～he decide to leave her. 她怕他決定拋棄她。I was afraid～he should come too late. 我怕他來得太晚。