中国大学MOOC: Choose a coordinating conjunction or a subordinating conjunction to combine each pair of simple sentences.(1)The number of school bus casualty is not large.(2)The safety of children is always of intense public concern.

Choose a coordinating conjunction or a subordinating conjunction to combine each pair of simple sentences.(1)Children overcome challenges on their own.(2)They develop new skills and a strong belief in their abilities. A: when B: unless C: becauae D: as

‌Choose a coordinating conjunction or a subordinating conjunction to combine each pair of simple sentences.‌‌(1)Children overcome challenges on their own.‌‌(2)They develop new skills and a strong belief in their abilities.‌‌‌ A: when B: unless C: becauae D: as

中国大学MOOC: Choose a coordinating conjunction or a subordinating conjunction to combine each pair of simple sentences.（1）Hotel guests have their meals free.（2）They naturally go to the free dining rooms to have their meals.

​Choose a coordinating conjunction or a subordinating conjunction to combine each pair of simple sentences.‏​(1)The number of school bus casualty is not large.‏​(2)The safety of children is always of intense public concern.‏​‏ A: although B: when C: unless D: because