Your teacher can identify your mistakes and difficulties – which will be associated with your mother language – and then tailor your exercises and homework assignments in order to tackle your specific pronunciation problems. Once you know which sounds you are not pronouncing clearly enough to be understood, you can work on the right position of your lips and tongue to produce the right sounds, and little tips or tricks when you can’t. For example, if your “l” gives you trouble, you might get away by pronouncing it almost as an “o” in some specific words (such as “will” or “well”), but other words like “usually” will not sounds understandable at all until you manage to pronounce your “l” clearly enough – a common issue among Chinese students. Likewise, pronouncing the “i” in the word ship as an “ee” sound will throw your listener off, who will think that you are saying the word sheep instead – which is a common issue among Spanish speakers.
Pronunciation skills can only be learned and mastered over a period of time, not instantly, and a teacher can help you learn patterns and tell you what sounds and linkages you need to work on and how; how to merge sounds and how to pronounce the resulting sound of a merge; what sounds you must pronounce and which ones you can skip altogether; and how to use intonation and word stress as a foot-hold to help your pronunciation.
Pronunciation and listening skills are closely related: as you improve one of them, the other one improves too, because both skills are based on learning to discriminate, recognize and produce certain sounds. So, it makes sense to work on both of them – pronunciation and listening – simultaneously, and your teacher can help you.
Working on connected speech is a mental and physical exercise, and it requires practice to be able produce difficult or new sounds “automatically.” Your teacher can coach you so you can practice on your own.
By working on word linking your pronunciation will improve, your speech will flow better, and people will understand you.