例：基数词在句中可作主语、宾语、定语、表语、同位语。

　　The two happily opened the box.(作主语)

　　I need three altogether.(作宾语)

　　Four students are playing volleyball outside.(作定语)

　　We are sixteen.(作表语)

　　They three tried to finish the task before sunset.(作同位语)

　　拓展：常见的数字符号和等式的读法：=(等于号)读作 equals，+(加号)读作 plus或and，-(减号)读作minus，×(乘号)读作times 或multiplied by，÷(除号)读作divided by。

　　例：3+2=5读作Three plus two equals(或is)five./Three and two is(或equals)five./Three and two makes five.

　　5-3=2读作 Five minus three equals(或is)two.

　　8×7=56读作Eight times seven equals(或is)fifty-six./Eight multiplied by seven is fifty-six.

　　10÷5=2读作Ten divided by five equals(或is)two.