Be sure, though, that what you refer to is clear. Perhaps this is what gives them both their air of happiness and freedom in these activities. Pronouns such as he, she, it, we, they and the like also refer back. Thus, they too provide links between sentences. The process of learning is essential to our lives.
All higher animals seek it deliberately.
They are inquisitive and they experiment. You may obtain a list of these phrases and their meaning from the Writing Center, and you may find them in most grammar handbooks. They too contribute to coherent writing, but they should be used sparingly. Now we need to be sure that we understand and can recognize these devices. At least one of each can be found in the following paragraph.