Task: Question Answering
Input (English): Passage: The company, retaining the title "Sadler's Wells Opera", opened at the Coliseum on 21 August 1968, with a new production of Mozart's Don Giovanni, directed by Sir John Gielgud. Though this production was not well received, the company rapidly established itself with a succession of highly praised productions of other works. Arlen died in January 1972, and was succeeded as managing director by Lord Harewood.The success of the 1968 Mastersingers was followed in the 1970s by the company's first Ring cycle, conducted by Goodall, with a new translation by Andrew Porter and designs by Ralph Koltai.  The cast included Norman Bailey, Rita Hunter and Alberto Remedios. In Harewood's view, among the highlights of the first ten years at the Coliseum were the Ring, Prokofiev's War and Peace, and Richard Strauss's Salome and Der Rosenkavalier.
The company's musical director from 1970 to 1977 was Charles Mackerras. Harewood praised his exceptional versatility, with a range "from The House of the Dead to Patience." Among the operas he conducted for the company were Handel's Julius Caesar starring Janet Baker and Valerie Masterson; five Janáček operas; The Marriage of Figaro with pioneering use of 18th century performing style; Massenet's Werther; Donizetti's Mary Stuart with Baker; and Sullivan's Patience. The company took the production of the last to the Vienna Festival in 1975, along with Britten's Gloriana. Sir Charles Groves succeeded Mackerras as musical director from 1978 to 1979, but Groves was unwell and unhappy during his brief tenure. Starting in 1979, Mark Elder succeeded Groves in the post, and described Groves "immensely encouraging and supportive".A long-standing concern of Arlen and then Harewood was the need to change the company's name to reflect the fact that it was no longer based at Sadler's Wells theatre. Byam Shaw commented "The one major setback the Sadler's Wells Opera Company suffered from its transplant was that unheeding taxi drivers kept on taking their patrons up to Rosebery Avenue".Harewood considered it an elementary rule that "you must not carry the name of one theatre if you are playing in another one." Covent Garden, protective of its status, objected to the suggestion that the Sadler's Wells company should be called "The British National Opera" or "The National Opera", although neither Scottish Opera nor the Welsh National Opera opposed such a change. Eventually the British government decided the matter, and the title "English National Opera" was approved. The company's board adopted the new name in November 1974. In 1977, in response to demand for more opera productions in English provincial cities, a second company was established. It was based at Leeds in northern England, and was known as ENO North. Under Harewood's guidance, it flourished, and in 1981 it became an independent company, Opera North. 
Question: What is the first name of the person who unwell and unhappy during his brief tenure?
Output (English): Charles.