In search for a linguistic basis for the education of Chinese as a foreign language CFL in Denmark, we set up a new line of investigation into CFL. This research focuses on the phonetics and phonology of Mandarin Chinese as compared to Danish. Considering the sound systems of both languages, we note some differences and similarities. The most remarkable differences are: -Chinese has rhotic sounds (pinyin ch, zh, sh, r) but Danish does not -Chinese has affricates (c z ch zh tɕ j) but Danish does not What Danish shares with Chinese is the contrast between aspirated and plain consonants: pa-ba /pha pa/ ta-da /tha ta/ ka-ga / kha-ka/ For L2 acquisition it is held that same and new phonemes are (relatively) easy acquired, whereas similar but not identical sounds are difficult to learn. New sounds are initially mapped onto the L1 phoneme inventory (Kuhl 1991). For Danish, this would predict that the aspiration contrast is easily acquired because it already exists. It would also mean that the rhotics and the affricated are easily acquired because Danish has no similar equivalent. The classroom observation is, however, surprising: first year Danish student of Chinese have difficulties in producing tai-cai pair, but the majority of them have little difficulties in identifying/perceiving this pair (e.g. from the classroom observation, the 1st year students can tell the distinction between this pair). But when it comes to production, they have great difficulties. There is a discrepancy between the perception and production. We hypothesize that the phonological system and the variation in the pronunciation of <t> in Danish is responsible for the production difficulty and will in a production and a perception experiment where lie the categorical boundaries of the students between tai and cai in a series of experiments. Further we will investigate the perception and production of tone among Danish students, as well as the tone perception of Chinese native speakers (with and without exposure to Danish) when they perceive Danish accented Chinese. Of special interest is the neutral tone: without particular instruction, which pitch contours do the Danish learners of Chinese use on neutral tones and to what extent does their production match that of native speakers? Future research may include Norwegian and Swedish-accented Chinese and a comparison between the different Germanic accents of CFL. Reference Kuhl, P.K. (1991). Human adults and human infants show a ‘perceptual magnet effect’ for the prototypes of speech categories, monkeys do not. Perception & Psychophysics, 50, pp. 93-107.