<![CDATA[Abstract Learning English as foreign language is considered difficult because it has its own systems and aspects that completely different from our mother tongue, such as the grammar, pronunciation, vocabulary, and cultural background of the language. Vocabuary is an important skill since we can not deliver meaning without words. However, learning English is not dealing only on vocabulary but also on grammar. Learning grammar becomes important since grammar can determine meaning of sentences. In the level of University students, it is quite difficult to make the students master all of the theme on grammar in one semester. Moreover, if it comes to conditional sentences. This topic really relays on the understanding of concepts. Once the students catch the concept, they will be able to solve some problems relate with the topic easily. To build their capability on understanding a concept of such a topic, teacher needs to figure out the appropriate way. Think-pair-share seems to be a good way to teach conditional sentences. The method used in conducting this research is Classroom Action Research. The research was conducted on two cycles with total meetings were seven; three meetings were for tests, and four meetings were for treatment. Each cycle covered the step of planning, acting, observing, and reflecting. From the data collected by the researcher, it can be concluded that the capability on understanding grammar of the second semester students of university level was improved. The improvements cover two points, they are: (1) improvement on their mean score. Mean score of pre-test was 4.1875, mean score of post-test 1 was 5.9625, while mean score of post-test 2 was 7.225. (2) improvement of their attitude and behaviour. It can be seen from their improvement of their activeness, enjoyment, curiousity and knowledge.Key words: CAR, Grammar, Think-Pair-Share ]]>
