不能绑定到“formGroup”，因为它不是“form”的已知属性。在角4

i got the error like Can't bind to 'formGroup' since it isn't a known property of 'form'.but i import FormsModule, ReactiveFormsModule and declared in imports but i got same error please any one help me thanks my code is :i got the error like Can't bind to 'formGroup'