问题
选择题
A health care project can provide treatment ______ half the cost or less，______ the needs of the patient.
A．at；relied on
B．with；relying on
C．at；relying on
D．by；relies on
答案
答案：C
at cost“以成本价”；at half the cost“以半价”；rely on 后接了宾语“the needs of the patient”，而句中已有了谓语can provide，所以rely on 必须用非谓语动词的形式；treatment和 rely on之间是主动关系，应用现在分词的形式。