When a relative clause is to serve as an adverb, it takes the same form as when it is to serve as an inanimate noun, except that "ce" is omitted before a preposition: « Ils sont allés dîner, après quoi ils sont rentrés » ("They went out to eat, after which they went home"); « Ils ne se sont pas du tout parlé, ce qui me semblait étrange » ("They did not talk to each other at all, which seemed strange to me").