To keep something secret.
何かを秘密にする。 (Nanika o himitsu ni suru.)
"I’ll tell you a secret, but keep it under your hat."
"秘密を教えるけど、内緒にしておいて。" (Himitsu o oshieru kedo, **naisho ni shite oite**.)
to make progress in order to achieve something
feeling nervous or excited
to have sympathy for someone
to become very interested in traveling
To know something very well
to disagree or be in conflict with someone or something
