All done but can't work out why: 18d "Force knocks up bitches" is grouses. To grouse is to bitch but where is the force knocked up? 23a "African place forms line , pressing to s h a g boyfriends head off" Something to do with tangent ? 4d "Vomit put off one regular boozer " Barfly .OK a barfly is a regular boozer but the rest of the clue?