Many students learn vocabulary and try to put many words together to create a proper sentence. It amazes me how many words some of my students know, but they cannot create a proper sentence. The reason is because they didn't study phrases. When children learn a language, they learn both words and phrases together. Likewise, you need to study and learn phrases.
The English Phrase Useful section is a great example of making numerous sentences with a single phrase. So don't spend hours and hours learning many different words. Use that time to study phrases instead and you will be closer to English fluency.