马克病了.他是周日生的病.
become 从一种状态到另一种状态的转变,成为.上句中指从没病到生病的过程转变.
例：I became familiar with the city after being here for 2 years.来到这个城市两年后,我开始熟悉这里了.（从不熟悉到熟悉）