Choose the main idea in this paragraph.
Ships of long ago had many ways of sending signals. Sails were raised and lowered. Sometimes a shield or a basket filled with burning wood was raised to the top of a mast. Flags, lanterns, and firing cannons, were also used.
Question 9 options:
messages that ships sent
how ships sent signals
why cannons were used to send signals
1 answer
how ships sent signals