It's no secret to us, but he alone is in the dark. It means ____.
-- Are you familiar the music? -- Yes. The music is very familiarme, but I can’t remember when and where I heard it.
-----The old man wouldn’t stay at home for a rest even if it rained. ---- . He would feel sick if he stayed home for one day.
You can’t use the machine today because some parts this week.
The employee you have been thinking highly dishonest.
Though young, he succeeded in taking the machine skillfully and then put it together without any difficulty.