The children are always warned the street when the trafic light is red . a. not to cross b. to cross A: not to cross B: to cross

跨境电子商务的英文名称是（ ） A: Cross Border Commerce B: Cross border Trade C: Cross Border E-commerce D: Cross Border Communication

“cross this square”中“cross”的意思是

St. Andria Cross (The white cross on the blue background) represents _____________

St. George Cross (The red cross on the white background) represents___________.

Be careful when ______ the road. A: [A] crossing B: to cross C: cross

阅读下面SQL代码片段： DECLARE val; IF val IS NULL THEN SELECT 'val is NULL'; ELSE A: A.输出val is NULL B: B.输出val is not NULL C: C.语法错误 D: D.运行时出现异常

下列语句错误的是______ A: int val(20); B: exterm int val(20); C: const int val; D: extern const int val;

阅读下面SQL代码片段：DECLARE val;IF val IS NULLTHEN SELECT 'val is NULL';ELSE SELECT 'val is not NULL';END IF;下面选项中，关于运行结果的描述，正确的是（） A: 输出val is NULL B: 输出val is not NULL C: 语法错误 D: 运行时出现异常

选择具有att属性且属性值为包含val的字符串的E元素的选择符是() A: E[att="val"] B: E[att~="val"] C: E[att*="val"] D: E[att|="val"]