The Roman script has fewer letters than the sounds in some of the languages that use it. Some languages make up for the lack of letters by using diacritic marks, such as ă, â, á, é, í, î, ó, ẹ, ị, ọ, ụ, ã, ả, ẻ, ỉ, ỏ, ủ, ñ, č, ď, ě, í, ň, ř, š, ș, ť, ț, ú, ů, ž and đ. In effect, this increases the number of letters in their alphabet. Languages which use "some" of these characters are French, Czech, Polish, Magyar (Hungarian), Romanian, Spanish, Tagalog, Vietnamese, Esperanto, and Igbo. 