Events and processes happen or happen to you,esp.if they a are not planned: All sorts of unexpected things might happen. What's happening to us? 。If you are talking about sth.that is planned or arranged,you often use tale place: The wedding will take place in the church. Problems and difficulties arise and sth. that happens suddenly and unexpectedly. Arise is used in formal situation: Let's consider what kind of difficulties might arise form the situation• Events and processes happen or happen to you, esp. if they are not planned: All sorts of unexpected things might happen. What’s happening to us? • If you are talking about sth. that is planned or arranged, you often use tale place: The wedding will take place in the church. • Problems and difficulties arise and sth. that happens suddenly and unexpectedly. Arise is used in formal situation: Let’s consider what kind of difficulties might arise form the situation