Yes, that is exactly what you should tell them. 1  If two clauses are connected with a coordinating conjunction, it's a compound sentence. 2  If two clauses are connected with a subordinating conjunction, it's a complex sentence.
Trains were first- 1784, but cars weren't invented until 1890.
The history of the train will show that Richard Trevithick made the first steam tramway locomotive in 1804. In 1814, George Stephenson created the Blucher, the first steam locomotive meant for railway use. Early History of Railways.