Textbooks for learning languages tend to be quite serious and few include much language play - puns, jokes, rhymes and so on. This can make the process of learning a language somewhat lacking in excitement.
It doesn't have to be like that - you can take even very dull phrases and sentences and play around with them to make them more interesting and memorable.
For example, you could take a sentence like "The pen is on the table" and maybe start by changing the nouns - "The elephant is on the chair", then adding more detils - "The blue elephant is on the green chair". You could also change the tense, add more elements to the sentence, make it into a question - "Was the blue elephant standing on the green chair scared of the enormous orange mouse?", and much more.
This kind of thing is a good way to practise manipulating the language, if you use unusual combinations of objects, situations, actions, and so on, you're more likely to remember not only the words themselves, but also the grammatical patterns and sentence structures.
Books for children in the language you're learning are a good place to find language play like this, as well as made-up words and ways of writing sounds.
This is just one way to make your studies more enjoyable, and will probably help you to remember what you're learning better and to look forward to studying, rather than seeing it as a necessary but perhaps dull activity.