凭空

out of thin air; baselessly; groundlessly; without foundation; without cause; from nowhere

出现

appear; emerge; arise; occur; surface; arrive; eclipse; show; come; make; take; start; form; happen; develop; figure; present; produce; walk; run; stage; raise; born; begin; touch; loom; spring; sprout; flash; manifest; materialize; come out; play out; show up; turn up; crop up; come up; open up; start up; present itself; offer itself; come along; come to pass; make an appearance; come into existence; come on the scene; raise its head; bring forth; float around; heave into sight; heave into view; rear its head; up; out; around; appearance; presence; emergence; occurrence; visitation; advent; stirring; birth; arrival