例如:There is a dictionary on the desk.(桌子上有一本字典。)
例如:There isn’t a dictionary on the desk.(桌子上没有字典。)
例如:Is there a dictionary on the desk?(桌子上有一本字典吗?)
例如:How many dictionaries are there on the desk?(桌子上有几本字典?)
What’s there on the desk?(桌子上有什么?)
例如:There is a dictionary on the desk, isn't there?(桌子上有一本字典,是吗?)