单项选择题
International trade gives consumers and countries the opportunity to（） goods andservices not available in their own countries.
A.expose to B.be exposing to C.be exposed to
单项选择题 Afterhavingseenthe（）andsamples，Jennymakesthespecificinquiry.
单项选择题 Thepaymentismadebyanirrevocable（）letterofcreditinourfavor.
单项选择题 （）youhavesaidisveryimportanttous.
