public boolean handleFirstExpression(Expr expr1, Expr expr2){
		if (expr1 instanceof LogicalExpr){
			Expr lhs1 = ((LogicalExpr) expr1).getLHS();
			Expr rhs1 = ((LogicalExpr) expr1).getRHS();
			String op1 = ((LogicalExpr) expr1).getOperator();
			
			if (op1.equals("and")){
				return handleFirstExpression(lhs1, expr2) && handleFirstExpression(rhs1, expr2);
			}else{ //op.equals("or")
				return handleFirstExpression(lhs1, expr2) || handleFirstExpression(rhs1, expr2);
			}
		}else{ //if (expr1 instanceof EqualityExpr) oder (expr1 instanceof RelationalExpr)
			return handleSecondExpression(expr2, expr1);
		}
	}