People with expressive aphasia typically perceive and read speech better than they can generate speech and write. The person's writing will be effortful, lack cohesiveness, and contain largely substance terms, similar to their speaking. They may produce letters and words in an attempt to communicate, but these will most likely be incorrect. Those with receptive aphasia tend to suffer more severe impairment in reading and writing than those with expressive aphasia. In this case, the patient cannot understand what is being said but can write down what they hear. They may make some attempts to communicate by spelling out words that are heard, or simply drawing pictures. But the quality of such efforts is very poor and cannot be considered meaningful. Individuals with conduction aphasia experience difficulty expressing themselves due to language impairments, but within their limitations, they are able to write. Words may come into their head but finding the right ones is often difficult. Sentences may be constructed but they usually make little sense and are not understood by others. People with global aphasia are unable to write due to extensive language impairment. Even if they could find the right words, they could not put them together into sentences or paragraphs. Their written communications would be meaningless babble.