A．Arrange objects according to the colour.
B．Tell one object from another.
C．Collect and store thousands of seeds in autumn, and find them later in winter.
D．Combine words in the right order.

A．There isn’t a room available at that time.
B．A speaker is coming to address the students.
C．Language testing will take longer than expected.
D．Lunch will not be ready until much later.