under pressure

　　I am under a lot of pressure

　　under one's breath

　　They are talking under their breath in the movie theater.

　　under a cloud

　　She has been under a cloud of depression since her dog died.

　　under the weather

　　I'm feeling a bit under the weather.

　　under arrest

　　You're under arrest.

　　That man was under arrest for robbing a bank.

　　under cover

　　The police officer went under cover to look for the drug dealers.

　　under one's nose

　　He flirted with a girl under his wife's nose.