Trainee language teachers can find it an uphill struggle to convince school colleagues that their subject is important, according to inspectors.
An Ofsted report on trainee primary language teachers said the students were enthusiastic and creative, but needed more support.
"They needed, at times, to adopt a somewhat evangelical role in their school placements," Ofsted said. "Sometimes they also had to convince their peers and, very occasionally, other tutors of the value of the subject."
Inspectors also identified transition to secondary schools as a key concern. Last week, The TES revealed research showing that children's progress in learning languages in primary schools risked being undermined when they reached secondary because of the lack of information-sharing.
Languages are due to become a compulsory part of the key stage 2 curriculum in 2011, and initial teacher-training courses for future language specialists have grown rapidly during the past six years.
In September 2001, five institutions began to offer a pilot primary language course to 40 trainees. Since then, 3,000 have undergone training and more than 38 providers now offer the courses.
Inspectors visited a sample of 10 training colleges and 38 schools last year. Trainees doing a language specialism - usually French or Spanish - do one placement abroad and one in England.
Inspectors found that trainees gained significantly in confidence as a result of their experiences abroad, but that in England trainees were sometimes limited because schools were still developing their foreign languages work. Students were also sometimes unaware of which languages pupils could already speak.
The report said trainees were good at motivating pupils, but less successful at planning, assessment and preparing pupils for secondary school.
The Ofsted report concluded that: "Providers' response to this final issue (transition to secondary school), in particular, will determine whether or not the primary languages initiative is ultimately successful."
Lander Road Primary in Liverpool has been teaching pupils Spanish for five years.
Barbara Billingsley, its head, said: "The trainees do come in full of enthusiasm for their specialism. I believe our staff can learn from trainees, particularly in modern foreign languages."
Wilkes Green Junior School in Birmingham has also been impressed by its trainees. It had two last year, one of whom taught French and the other Spanish. Avtar Singh Mangat, its headteacher, said the school was unable to offer language lessons at the moment, but hoped to do so again.
"We had started teaching French, but unfortunately we had to stop because the teacher left. Then we worked with the secondary school for a limited time," he said. "However, we do have Punjabi classes after school which are attended not only by Punjabi-speaking children but by other children."
Primary languages in initial teacher training, www.ofsted.gov.uk.