Okay, imagine you're building a castle with building blocks. A dependent clause is like a little section of your castle that needs to lean on another section to stand up properly.
Let's say you're building a tower out of blocks, but you need to put some support on the bottom to make sure it doesn't fall over. That support is like a dependent clause. It's a smaller part of the tower that can't stand up by itself, but is important for the whole tower to work.
In language, a dependent clause is like a group of words that isn't a complete sentence on its own, but it needs to be attached to the rest of the sentence to make sense. It's like a helper part of a sentence that doesn't work alone. Just like how the blocks in your tower need each other to be strong and stand up tall.