单项选择题
It is not easy to learn English well, but if you ______, you will succeed in the end.
单项选择题 My cousin likes eating very much, but he isn't very ______ about the food he eats.
单项选择题 Cancer is second only ______ heart disease as a cause of death.
单项选择题 Cut off by the storm, they were forced to ______ food for several.
